1 2 GNU GENERAL PUBLIC LICENSE 3 Version 2, June 1991 4 5 Copyright (C) 1989, 1991 Free Software Foundation, Inc. 6 675 Mass Ave, Cambridge, MA 02139, USA 7 Everyone is permitted to copy and distribute verbatim copies 8 of this license document, but changing it is not allowed. 9 10 Preamble 11 12 The licenses for most software are designed to take away your 13 freedom to share and change it. By contrast, the GNU General Public 14 License is intended to guarantee your freedom to share and change free 15 software--to make sure the software is free for all its users. This 16 General Public License applies to most of the Free Software 17 Foundation's software and to any other program whose authors commit to 18 using it. (Some other Free Software Foundation software is covered by 19 the GNU Library General Public License instead.) You can apply it to 20 your programs, too. 21 22 When we speak of free software, we are referring to freedom, not 23 price. Our General Public Licenses are designed to make sure that you 24 have the freedom to distribute copies of free software (and charge for 25 this service if you wish), that you receive source code or can get it 26 if you want it, that you can change the software or use pieces of it 27 in new free programs; and that you know you can do these things. 28 29 To protect your rights, we need to make restrictions that forbid 30 anyone to deny you these rights or to ask you to surrender the rights. 31 These restrictions translate to certain responsibilities for you if you 32 distribute copies of the software, or if you modify it. 33 34 For example, if you distribute copies of such a program, whether 35 gratis or for a fee, you must give the recipients all the rights that 36 you have. You must make sure that they, too, receive or can get the 37 source code. And you must show them these terms so they know their 38 rights. 39 40 We protect your rights with two steps: (1) copyright the software, and 41 (2) offer you this license which gives you legal permission to copy, 42 distribute and/or modify the software. 43 44 Also, for each author's protection and ours, we want to make certain 45 that everyone understands that there is no warranty for this free 46 software. If the software is modified by someone else and passed on, we 47 want its recipients to know that what they have is not the original, so 48 that any problems introduced by others will not reflect on the original 49 authors' reputations. 50 51 Finally, any free program is threatened constantly by software 52 patents. We wish to avoid the danger that redistributors of a free 53 program will individually obtain patent licenses, in effect making the 54 program proprietary. To prevent this, we have made it clear that any 55 patent must be licensed for everyone's free use or not licensed at all. 56 57 The precise terms and conditions for copying, distribution and 58 modification follow. 59 60 GNU GENERAL PUBLIC LICENSE 61 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 62 63 0. This License applies to any program or other work which contains 64 a notice placed by the copyright holder saying it may be distributed 65 under the terms of this General Public License. The "Program", below, 66 refers to any such program or work, and a "work based on the Program" 67 means either the Program or any derivative work under copyright law: 68 that is to say, a work containing the Program or a portion of it, 69 either verbatim or with modifications and/or translated into another 70 language. (Hereinafter, translation is included without limitation in 71 the term "modification".) Each licensee is addressed as "you". 72 73 Activities other than copying, distribution and modification are not 74 covered by this License; they are outside its scope. The act of 75 running the Program is not restricted, and the output from the Program 76 is covered only if its contents constitute a work based on the 77 Program (independent of having been made by running the Program). 78 Whether that is true depends on what the Program does. 79 80 1. You may copy and distribute verbatim copies of the Program's 81 source code as you receive it, in any medium, provided that you 82 conspicuously and appropriately publish on each copy an appropriate 83 copyright notice and disclaimer of warranty; keep intact all the 84 notices that refer to this License and to the absence of any warranty; 85 and give any other recipients of the Program a copy of this License 86 along with the Program. 87 88 You may charge a fee for the physical act of transferring a copy, and 89 you may at your option offer warranty protection in exchange for a fee. 90 91 2. You may modify your copy or copies of the Program or any portion 92 of it, thus forming a work based on the Program, and copy and 93 distribute such modifications or work under the terms of Section 1 94 above, provided that you also meet all of these conditions: 95 96 a) You must cause the modified files to carry prominent notices 97 stating that you changed the files and the date of any change. 98 99 b) You must cause any work that you distribute or publish, that in 100 whole or in part contains or is derived from the Program or any 101 part thereof, to be licensed as a whole at no charge to all third 102 parties under the terms of this License. 103 104 c) If the modified program normally reads commands interactively 105 when run, you must cause it, when started running for such 106 interactive use in the most ordinary way, to print or display an 107 announcement including an appropriate copyright notice and a 108 notice that there is no warranty (or else, saying that you provide 109 a warranty) and that users may redistribute the program under 110 these conditions, and telling the user how to view a copy of this 111 License. (Exception: if the Program itself is interactive but 112 does not normally print such an announcement, your work based on 113 the Program is not required to print an announcement.) 114 115 These requirements apply to the modified work as a whole. If 116 identifiable sections of that work are not derived from the Program, 117 and can be reasonably considered independent and separate works in 118 themselves, then this License, and its terms, do not apply to those 119 sections when you distribute them as separate works. But when you 120 distribute the same sections as part of a whole which is a work based 121 on the Program, the distribution of the whole must be on the terms of 122 this License, whose permissions for other licensees extend to the 123 entire whole, and thus to each and every part regardless of who wrote it. 124 125 Thus, it is not the intent of this section to claim rights or contest 126 your rights to work written entirely by you; rather, the intent is to 127 exercise the right to control the distribution of derivative or 128 collective works based on the Program. 129 130 In addition, mere aggregation of another work not based on the Program 131 with the Program (or with a work based on the Program) on a volume of 132 a storage or distribution medium does not bring the other work under 133 the scope of this License. 134 135 3. You may copy and distribute the Program (or a work based on it, 136 under Section 2) in object code or executable form under the terms of 137 Sections 1 and 2 above provided that you also do one of the following: 138 139 a) Accompany it with the complete corresponding machine-readable 140 source code, which must be distributed under the terms of Sections 141 1 and 2 above on a medium customarily used for software interchange; or, 142 143 b) Accompany it with a written offer, valid for at least three 144 years, to give any third party, for a charge no more than your 145 cost of physically performing source distribution, a complete 146 machine-readable copy of the corresponding source code, to be 147 distributed under the terms of Sections 1 and 2 above on a medium 148 customarily used for software interchange; or, 149 150 c) Accompany it with the information you received as to the offer 151 to distribute corresponding source code. (This alternative is 152 allowed only for noncommercial distribution and only if you 153 received the program in object code or executable form with such 154 an offer, in accord with Subsection b above.) 155 156 The source code for a work means the preferred form of the work for 157 making modifications to it. For an executable work, complete source 158 code means all the source code for all modules it contains, plus any 159 associated interface definition files, plus the scripts used to 160 control compilation and installation of the executable. However, as a 161 special exception, the source code distributed need not include 162 anything that is normally distributed (in either source or binary 163 form) with the major components (compiler, kernel, and so on) of the 164 operating system on which the executable runs, unless that component 165 itself accompanies the executable. 166 167 If distribution of executable or object code is made by offering 168 access to copy from a designated place, then offering equivalent 169 access to copy the source code from the same place counts as 170 distribution of the source code, even though third parties are not 171 compelled to copy the source along with the object code. 172 173 4. You may not copy, modify, sublicense, or distribute the Program 174 except as expressly provided under this License. Any attempt 175 otherwise to copy, modify, sublicense or distribute the Program is 176 void, and will automatically terminate your rights under this License. 177 However, parties who have received copies, or rights, from you under 178 this License will not have their licenses terminated so long as such 179 parties remain in full compliance. 180 181 5. You are not required to accept this License, since you have not 182 signed it. However, nothing else grants you permission to modify or 183 distribute the Program or its derivative works. These actions are 184 prohibited by law if you do not accept this License. Therefore, by 185 modifying or distributing the Program (or any work based on the 186 Program), you indicate your acceptance of this License to do so, and 187 all its terms and conditions for copying, distributing or modifying 188 the Program or works based on it. 189 190 6. Each time you redistribute the Program (or any work based on the 191 Program), the recipient automatically receives a license from the 192 original licensor to copy, distribute or modify the Program subject to 193 these terms and conditions. You may not impose any further 194 restrictions on the recipients' exercise of the rights granted herein. 195 You are not responsible for enforcing compliance by third parties to 196 this License. 197 198 7. If, as a consequence of a court judgment or allegation of patent 199 infringement or for any other reason (not limited to patent issues), 200 conditions are imposed on you (whether by court order, agreement or 201 otherwise) that contradict the conditions of this License, they do not 202 excuse you from the conditions of this License. If you cannot 203 distribute so as to satisfy simultaneously your obligations under this 204 License and any other pertinent obligations, then as a consequence you 205 may not distribute the Program at all. For example, if a patent 206 license would not permit royalty-free redistribution of the Program by 207 all those who receive copies directly or indirectly through you, then 208 the only way you could satisfy both it and this License would be to 209 refrain entirely from distribution of the Program. 210 211 If any portion of this section is held invalid or unenforceable under 212 any particular circumstance, the balance of the section is intended to 213 apply and the section as a whole is intended to apply in other 214 circumstances. 215 216 It is not the purpose of this section to induce you to infringe any 217 patents or other property right claims or to contest validity of any 218 such claims; this section has the sole purpose of protecting the 219 integrity of the free software distribution system, which is 220 implemented by public license practices. Many people have made 221 generous contributions to the wide range of software distributed 222 through that system in reliance on consistent application of that 223 system; it is up to the author/donor to decide if he or she is willing 224 to distribute software through any other system and a licensee cannot 225 impose that choice. 226 227 This section is intended to make thoroughly clear what is believed to 228 be a consequence of the rest of this License. 229 230 8. If the distribution and/or use of the Program is restricted in 231 certain countries either by patents or by copyrighted interfaces, the 232 original copyright holder who places the Program under this License 233 may add an explicit geographical distribution limitation excluding 234 those countries, so that distribution is permitted only in or among 235 countries not thus excluded. In such case, this License incorporates 236 the limitation as if written in the body of this License. 237 238 9. The Free Software Foundation may publish revised and/or new versions 239 of the General Public License from time to time. Such new versions will 240 be similar in spirit to the present version, but may differ in detail to 241 address new problems or concerns. 242 243 Each version is given a distinguishing version number. If the Program 244 specifies a version number of this License which applies to it and "any 245 later version", you have the option of following the terms and conditions 246 either of that version or of any later version published by the Free 247 Software Foundation. If the Program does not specify a version number of 248 this License, you may choose any version ever published by the Free Software 249 Foundation. 250 251 10. If you wish to incorporate parts of the Program into other free 252 programs whose distribution conditions are different, write to the author 253 to ask for permission. For software which is copyrighted by the Free 254 Software Foundation, write to the Free Software Foundation; we sometimes 255 make exceptions for this. Our decision will be guided by the two goals 256 of preserving the free status of all derivatives of our free software and 257 of promoting the sharing and reuse of software generally. 258 259 NO WARRANTY 260 261 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 262 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 263 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 264 PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 265 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 266 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 267 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 268 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 269 REPAIR OR CORRECTION. 270 271 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 272 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 273 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 274 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 275 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 276 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 277 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 278 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 279 POSSIBILITY OF SUCH DAMAGES. 280 281 END OF TERMS AND CONDITIONS 282 283 Appendix: How to Apply These Terms to Your New Programs 284 285 If you develop a new program, and you want it to be of the greatest 286 possible use to the public, the best way to achieve this is to make it 287 free software which everyone can redistribute and change under these terms. 288 289 To do so, attach the following notices to the program. It is safest 290 to attach them to the start of each source file to most effectively 291 convey the exclusion of warranty; and each file should have at least 292 the "copyright" line and a pointer to where the full notice is found. 293 294 <one line to give the program's name and a brief idea of what it does.> 295 Copyright (C) 19yy <name of author> 296 297 This program is free software; you can redistribute it and/or modify 298 it under the terms of the GNU General Public License as published by 299 the Free Software Foundation; either version 2 of the License, or 300 (at your option) any later version. 301 302 This program is distributed in the hope that it will be useful, 303 but WITHOUT ANY WARRANTY; without even the implied warranty of 304 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 305 GNU General Public License for more details. 306 307 You should have received a copy of the GNU General Public License 308 along with this program; if not, write to the Free Software 309 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 310 311 Also add information on how to contact you by electronic and paper mail. 312 313 If the program is interactive, make it output a short notice like this 314 when it starts in an interactive mode: 315 316 Gnomovision version 69, Copyright (C) 19yy name of author 317 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 318 This is free software, and you are welcome to redistribute it 319 under certain conditions; type `show c' for details. 320 321 The hypothetical commands `show w' and `show c' should show the appropriate 322 parts of the General Public License. Of course, the commands you use may 323 be called something other than `show w' and `show c'; they could even be 324 mouse-clicks or menu items--whatever suits your program. 325 326 You should also get your employer (if you work as a programmer) or your 327 school, if any, to sign a "copyright disclaimer" for the program, if 328 necessary. Here is a sample; alter the names: 329 330 Yoyodyne, Inc., hereby disclaims all copyright interest in the program 331 `Gnomovision' (which makes passes at compilers) written by James Hacker. 332 333 <signature of Ty Coon>, 1 April 1989 334 Ty Coon, President of Vice 335 336 This General Public License does not permit incorporating your program into 337 proprietary programs. If your program is a subroutine library, you may 338 consider it more useful to permit linking proprietary applications with the 339 library. If this is what you want to do, use the GNU Library General 340 Public License instead of this License.